Identification of a thermophilic bacterium and preliminary characterization of the secreted xylanase

Abstract:

The bacterium isolated from a water sample of Yunnan tengchong hot spring can secrete a kind of thermophilic xylanase. It was identified and named as Geobacillus sp. PZH1 by morphologic observation, physio-biochemical characteristics and 16S rDNA sequence alignment. Subsequently, its secreted xylanase and the xylanase’s characteristics were researched preliminarily. SDS-PAGE electrophoresis and zymogram analysis suggested that the xylanase’s molecular mass was 69 kD; the optimum pH and temperature of the partially purified enzyme were 7.0 and 70 °C respectively, and it performed noted activities from pH 5.0 to pH 11.0 and from 40 °C to 100 °C; it had high stability from pH 5.0 to pH 12.0 and under 70 °C; from 40 °C to 100 °C, no cellulase activity was detected for the partially purified xylanase.